The invention relates to a multipart chain fixing device for temporarily blocking at least one conveyor chain on a trough element of a chain conveyor, in particular of an underground scraper chain conveyor, comprising a bridge part, which has a bridge bar that at least partially overlaps the conveyor chain in a positive-locking manner and ends in two lateral side end portions, and comprising two side parts, which can be fastened to the trough pan and to which the side end portions of the bridge part can be releasably secured by positive-locking means. The invention further relates to a trough element for a chain conveyor, in particular an underground scraper chain conveyor, comprising an upper strand, comprising a lower strand, comprising side profiles for guiding driver elements of a conveyor chain, comprising a conveyor floor separating the upper strand and the lower strand, preferably comprising an intermediate floor beneath the conveyor floor, and comprising a device for applying a chain fixing device. Finally, the invention also relates to the associated bridge part or the associated side parts for the chain fixing device.
DE 298 06 629 U1 discloses a chain fixing device in which, on the bridge part and on the side parts, recesses such as, for example, a central pass-through opening in the bridge portion of the bridge part, cutouts on the bottom side of the bridge part, a purely one-sided, positive-locking stop wall for the chain links in the direction of pull, and recesses on the rear and bottom sides of the side parts are provided in order to enhance the ease of handling of the chain fixing device by lightening of the weight. In order to reduce the weight of the bridge, it is further provided that the side end portions are configured as tongues, which engage in side slits within the side parts. For the fixing of the bridge, those end faces of the tongues which point in the direction of pull butt against a front wall which bounds the side slit in the direction of pull. The side parts can be bolted to the trough side profiles by means of lock pins and the tongue-like side end portions of the bridge can be secured within the side slits by means of further lock pins.
Where this chain fixing device is used in underground scraper chain conveyors, particularly when the trough side profiles of the conveyor trough are already exhibiting low to medium wear, an unfavourable widening of those plug-in openings by which the side parts are fixed relative to the trough side profiles can occur. This leads to excessive wear and to non-usability of the respective trough pan, although the trough side profiles of the trough pan would still be functional. In addition, the rear-side openings of the chain link receptacles, which openings are provided in the chain fixing device according to DE 298 06 629 U1, pose a threat to the staff underground, since, in the event of a chain breakage of the horizontal chain link received in a positive-locking manner by the bridge part, a spring-back of the chain can arise.